This invention relates to a cathodic electrodeposition paint. When a number of metallic substrates are successively coated with an electrodeposition paint while conveying the substrates along a coating line including various operational stations, oil droplets or mist necessarily entrained in air currents or scattered from associated machines may degrade the quality of the finish. This is because oil droplets deposited on the wet paint film before or during the baking operation radially expel an amount of paint to produce a number of tiny craters.
Methods are known to prevent oil droplet-induced craters from forming including the incorporation of kaolin or other flaky body pigments into the paint formulation to increase the pigment concentration and/or the use of high molecura weight vehicle resins to decrease the paint fluidity. These known methods, however, must suffer from decrease in smoothness of the cured paint film in terms of average surface roughness commonly represented by the notation Ra.
Accordingly, a need exists for a cathodic electrodeposition paint which is hardly susceptible to oil droplet-induced craters without compromising the surface smoothness of the cured paint film.